Method of and mechanism for operating the picking stick of mechanical looms



March 27, 1956 C SELLES 2,739,620

METHOD OF AND MECHANISM FOR OPERATING THE PICKING STICK OF MECHANICAL LOOMS 3 Sheets-Sheet 1 Filed NOV. 14, 1952 I N VEN TOR PEDRO CERDANS'SELLES BY WQMQUL .HMKRrg mat P. C. SELLES METHOD OF AND MECHANISM FOR OPERATING THE PICKING STICK OF MECHANICAL LOOMS March 27, 1956 3 Sheets-Sheet 2 Filed NOV. 14, 1952 INVENTOR PEDRO CERDANS SELLES BY Mud 06L 6. fln'wim.

March 27, 1956 P. c. SELLES METHOD OF AND MECHANISM FOR OPERATING THE PICKING STICK OF MECHANICAL LOOMS 3 Sheets-Sheet 3 Filed NOV. 14, 1952 FIG.4

INVENTOR PEDRO CERDANS SELLES METHOD OF AND MECHANISM FOR OPERATING THE PICKING STICK OF MECHANIAL LOOMS Pedro Cerdans Selles, Barcelona, Spain Application November 14, 1952, Serial No. 320,435 Claims priority, application Spain November 16, 1951 6 Claims. (Cl. 139-145) This invention relates to a method of and mechanism for operating the picking stick in mechanical looms, which is a substantial improvement upon hitherto known systems and introduces an entirely difierent mechanical conception in this class of mechanism and which results in an improved performance of the loom as regards general operation.

Hitherto the operation of the picking stick in looms has always been effected by direct action mechanisms, i. e., eccentrics, levers, connecting rods, and the like, which at the appropriate moment cause a rapid and powerful movement of the picking stick in order that the latter may effect the expulsion of the shuttle. In all previously known mechanisms, the difiiculty has arisen of solving the problem of imparting abruptly and at a given moment a powerful impulse to an element which until that moment was at rest, namely the picking stick and shuttle, that is to say an excess of absorbed power is required at the precise moment of the impulsion, While there are abrupt changes of resistance, which results in defective movements, defective operation, and deterioration.

It is an object of the present invention to obviate the foregoing drawbacks by driving the picking stick indirectly through power accumulated during the entire period in which the picking stick is at rest and releasing this power at the appropriate moment to actuate the picking stick.

To this end, the present invention consists in a method of operating the picking stick of a mechanical loom, which comprises storing power by twisting a torsion bar through a suitable transmission from a main shaft or spindle of the loom, during the period in the cycle of operation of the loom in which the picking stick is inoperative, and at the appropriate moment releasing the torsion in said bar and utilising the stored power to operate the picking stick through said transmission.

The invention also provides a drive mechanism for the picking stick of a mechanical loom, which comprises a member fast with the picking stick and connected to a rocking member, a torsion bar fast with said rocking member, eccentric means actuated from a main shaft of the loom for operating said rocking part through a tie rod and a slide, the profile of said eccentric means being so shaped that the tie-rod and the slide drive the rocking part during the period in the cycle of the loom in which the picking stick is inoperative to twist the torsion bar, stop means for retaining said rocking part in a position where the torsion bar is held under potential load, and means associated with said tie-rod to disengage said stop means at the appropriate moment to free the rocking part and release the torsion bar load to drive the picking stick.

In order that the invention may be more readily understood, reference is made to the accompanying drawings, which illustrate diagrammatically and by way of example, one embodiment thereof, and in which:

Figure 1 is a side elevation of a picking stick drive mechanism;

2,739,620 Patented Mar. 27, 1956 Figure 2 is a front view thereof, viewed from the torsion bar side;

Figure 3 is a diagrammatic view of the picking stick; and

Figure 4 is a sectional view of a gear transmission connecting the picking shaft with the driving mechanism of the torsion bar;

Fig. 5 is a front view of the driving mechanism, and Fig. 6 is a side view of the driving mechanism.

A metal picking stick 1, which is integral with its picker 2, is secured by tie-rods 3 and nuts 4 to a member 5, which has central grooves 6 (Figures 2 and 3). The member 5 is connected by a roller 7 to a curved slot 8 on a fixed part 9, and at the same time the member 5 can be displaced axially on slides 10 and 11 engaging the grooves 6. Slides 10 and 11 are fast with a part 12, and the latter in turn is solid with a torsion bar 13 bearing at its end on a fixed bushing 14, while the two elements are connected together by means of a spring 15. The part 12 has resilient shoes 16 for damping the shocks against stops 17 provided on a part 18, the position of which is adjustable by means of a screw 19, so that in this manner the stops and shoes can be moved away or towards one another.

The part 12 has at the bottom a fork 20 with a pivot 21, which is introduced into a slot 22 in a sliding part 23.

The sliding part 23 is axially displaceable by a tie-rod 24, which in turn is operated by the eccentric 25 (Figures 5 and 6) through a roller 26. Eccentric 25 at the same time drives a roller 27 of another similar tie-rod 27' for the purpose of operating the other picking stick.

The part 12, which is solid with the torsion bar 13, has a projecting pivot 28 (Figure 2), which serves as retaining stop for said part when its toothed part 29 is placed on another toothed part 30 of a lever 31, which is articulated at 32 and connected to a lever 31' by means of a screw 32 and spring 33, lever 31' being operated by the tie-rod 24, in one direction through the medium of a spring 33' and in the other direction by a stop nut 34, the position of which is variable.

The torsion bar 13 is solidly fixed at its end to a bearing 35, and its torsion can be graduated by means of a screw 36 (Figure 1).

The eccentric 25 is driven by a shaft 37 (Figure 4), which is driven through a suitable transmission 38, 39 by the picking shaft 40 of the loom, while the angular position between 40 and 38 can be varied by a screw 41.

The mechanism functions in the following manner:

The picking shaft 40 drives the eccentric 25 through the bevel pinions 38 and 39, while through the rollers 26 and 27 the eccentric drives the tie-rods 24 and 27' transmitting the drive to the charging mechanisms of the torsion bars. These charging mechanisms act in the following manner: the tie-rod 24, through the slide 23, drives the rocking part 12 solid with the torsion bar 13 which, be ing fixed at the other end by means of the bearing 35, will be subjected to torsion. The same tie-rod 24 will also bring the end of the lever 31 near the pivot 28 solid with the part 12, and at the appropriate moment the tooth 29 of the pivot 28 will bear against the tooth 30 of the lever 31, the part 12 and the torsion bar 13 being thereby retained in the twisted position under tension, that is to say with stored power. When the tie-rod 24 returns, following the cycle of the eccentric 25 and in accordance with the movements of the loom, it will push by means of the stop nut 34 against the lever 31, separating the head of the latter from the pivot 28, and the torsion bar will be released. As the part 12 is connected to the part 5 carrying the picking stick 1, the latter will be operated on the release of the torsion bar, thereby effecting the expulsion of the shuttle.

At the appropriate moment, and through another identical mechanism operated by the tie-rod 27', the other picking stick will be operated and thus the working cycle of these mechanisms will berepeated successively.

The connection between the parts and 12 by means of the slots 6-and slides 10and ll'sliding inside the same,

and also because the part 5 is connected through pivot 7 picking stick 1, and consequently a rectilinear driving of the shuttle 37.

The stops 17 and resilient shoes 1,6.damp and limit the path of the part 12 when the; torsion bar is driven, and these movements can be adjusted by means of the screw 19. The initial torsion of the bar 13 can also be varied by the screw 36 of the bearing 35.

From the foregoing description of the functioning of the mechanism it will be seen that the torsion bar eiiects the driving of the picking stick by means of a storage of power therein, the loading taking place during the period in which the picking stick is inoperative.

I claim:

1. A method of operating the picking stick of a mechanical loom, which comprises storing power by twisting a torsion bar through a suitable transmission from a main shaft or spindle of the loom, during the period in the cycle of operation of the loom in which the picking stick is inoperative, blocking said transmission for retaining said torsion bar in a position adapted for storing power, and at the appropriate moment releasing said transmission and thereby the torsionin said bar and utilising the stored power to operate the picking stick through said transmission.

2. A drive mechanism for the picking stick of a mechanical loom, which comprises a member fast with the picking stick and connected to a rocking member, a torsion bar fast with said rocking member, eccentric means actuated from a main shaft of the loom for operating said rocking part through a tierod and a slide, the profile of said eccentric means being so shaped that the tie-rod and slide drive the rocking par-t during the period in the cycle of the loom in which the picking stick is inoperative to twist the torsion bar, stop means for retaining said rocking part in a position where the torsion bar is held under potential load, and means associated with said tierod to disengage said stop means at the appropriate moment to free the rocking part and release the torsion bar load to drive the picking stick.

3. Drive mechanism as claimed in claim 2, wherein the connection between the member carrying the picking stick and therocking part is efiected by means of slides and grooves which permit axial displacement between the two parts, combined with a rockable connection of the member carrying the picking stick about a curved fixed groove through a roller on said member which slides in said groove, said connections resulting in a rectilinear movement of the end of the picking stick.

4. Drive device as claimed in claim 2, which includes springs and damping stops disposed in the path of the release of the picking stick, and position and tension regulators for the torsion bar at both ends of the latter.

5. Drive mechanism as claimed in claim 2, wherein the stopmeans comprise a projection or pivot solid with rocking member and provided with a tooth which, on .a predetermined movement of the rocking member, comes into contact and. is retained by a lever, said lever being withdrawn from engagement with said tooth at the moment at which the shuttle has to be expelled.

6. A drive mechanism for the picking stick of a me-, chanical loom, comprising, in combination a torsion bar; a transmission connecting the main shaft of the m with the torsion bar for twisting the torsion bar during the period in the cycle of the loom in which the picking stick is inoperative; stop means for blocking said transmission in a position in which the torsion bar is held under potential load; andmeans connected to said transmission for disengaging said stop means at the appropriate moment to free the transmission so as to release the torsion bar load to drive the picking stick.

References Cited in the file of this patent UNITED STATES PATENTS 2,160,338 Moessinger May 30, 1939 2,160,339 Moessinger May 30, 19-39 FOREIGN PATENTS 678,468 Germany July 15, 1939. 

